Conventionally, as a mounting head that performs mounting of components onto a board, known is a head provided with a rotation plate formed on which are multiple slits with a slit angle θ that varies by each slit, nozzles of the mounting head arranged to correspond to the positions of the slits, and a control section registered with the angle θ between the above slits (for example, refer to patent literature 1). With this mounting head, it is possible to detect at high speed the origin position of the mounting head in the rotation direction. Also, there are is a known mounting head in which a rotation member is positioned at a response position of a sensor at the zero count position of the encoder used by the motor that rotationally drives the rotary head, and a reference spindle is directly below a pushing down member, the configuration being such that the angle of each spindle is zero at the zero count position of the encoder used by the motor that axially rotates each spindle. With this mounting head, it is possible to adjust the origin position without performing data backup.